GSoC project: Waveform generation element

Peteris Krisjanis pecisk at
Wed Mar 28 04:43:53 PDT 2012

T , 2012-03-28 12:48 +0200, Stefan Sauer wrote:
> >  One crazy idea is do the drawing
> > in C Cairo too, but that's probably overkill (and would require nice
> > set of features for developers to modify it according to their need).
> To me this sounds more like we want a wave-form gtk widget, which could
> have a model-view split. One model could use gst with the level element
> to build the waveform data, another one could peek at a waveform in
> memory, yet another one could build a sophisticated multi-zoom level
> structure (which hardly pays off these days anymore).

That's what I have been thinking about this proposal - gstreamer
waveform data part and drawing part in gtk.

> The view would do the drawing using cairo and could have a couple of
> options to customize the appearance. Be careful as here it gets
> complicated. Applications will most likely want to overlay this with:
> - selections
> - loop markers (section markers)
> - controller curves
> - ...

Yep, I will need this as Jokosher draws cursor and fade markers on
waveforms. I will have to expand my knowledge about Gtk, but it seems

Also I will have to think how to handle audio with multiple channels.

> > Currently I keep going trough materials provided by Jeff Fortin.
> Do you have a link?

These are your IRC #pitivi and email discussion logs in about waveforms
in general and in Pitivi. Jeff gave me this so I can read more what's
already been discussed (mostly about caching and .sfk type of files

In this definition now it seems reasonable GSoC project to propose,
thank you for comments.

Peteris Krisjanis

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